bonjiri wrote:the glaze is black (the one in japan)some kind of black ash is incorporated as the flux

The black is mainly from partially burnt rice husk ash (nuka) and the grey dobai (regular wood ash) that form a good portion of the glaze. The nuka is mainly added for the silica content.

My core recipe for nuka glaze is from Hamada Shoji.......

1/3 rice husk ash1/3 washed wood ash1/3 high silica feldspar

It too is almost black when wet....dark grey and chalky and firable when bone dry.

best,

.....................john

Thanks for the info Johh.Wish I could take a class from you in glaze formulation, etc. I only follow glaze recipies that I think will fit my pieces. The only true ash I use is Kingsford Briquette ash from my BBQ, unwashed no additives.

Interesting on the Kingsford. I JUST a few weeks ago decided to do some tests using that exact same stuff from my grill. Been saving it for testing. My understanding is that they add bentonite to the wood product to assist in the forming of the birquettes and them holding their shape. Don't know what else is added though.

Interesting on the Kingsford. I JUST a few weeks ago decided to do some tests using that exact same stuff from my grill. Been saving it for testing. My understanding is that they add bentonite to the wood product to assist in the forming of the birquettes and them holding their shape. Don't know what else is added though.

best,

..............john

Thanks for the kind words John.I don't study Chado, I attended a few and have a few friends that study and perform The Way Of Tea. That's where I pick up a few pointers for my work. I saw your post on Ceramics Arts Daily tea workshop, wish I could be there.Kingsford also adds limestone and borax besides a few other ingredients. It burns to a very fine dust so it's easy to sift and use.Here's a mizusashi with the Kingsford ash.

Thanks for the info on the Kingsford. More calcium oxide and a bit of sodium oxide and boron.... perfect.

NICE mizusashi.

Are you using real urushi on the wood lids or is that the Cahsew product? How are you controlling the humidity for the drying of the urushi?

I've been doing some limited wooden lids, but haven't "cracked" the urushi issue yet well at all.

best,

...............john

John, I'm not using urushi. I used to be an auto painter and tried all the auto paints the last 25 years on wood. I ended up using urethane, expensive but the must durable. Hope this doesn't change your views on my pieces.